Most of the world's population is concentrated in urban areas, where economic activity is concentrated. The world's urban areas are growing at an astonishing rate. The world's economy is a fascinating topic. Learn about urban, economic, and transportation geography from these resources.

* Largest Cities in the World * Defining Urban * Sectors of the Economy * Busiest Airports of the World * Busiest Ports of the World * Primate Cities * Megalopolis